On Nov 22, 2012, at 12:26 AM, Jan Wielemaker wrote:
> I guess we should not (re)start this discussion unless there is
> a concrete proposal to introduce strings as subjects. My quick
> intuition is that these are a few of the consequences that I don't
> like.
>
> - Invites for poor modelling
I have never found the suggested examples compelling, but in any case, this should be handled by good-use guides and tutorials rather than hardwired into the syntax.
> - Introduces interoperability issues
How so? (Do you mean with legacy systems: well yes, of course. But any change can be objected to on those grounds.)
> - Harms efficient reasoning. One of the nice things about
> resources is that you can compare them quickly. SPARQL
> Lit1 = Lit2 is a much more complicated beast.
Incomprehensible. Equality between literals is if anything easier to compute than between IRIs. The problem of establishing owl:sameAs between two IRIs is probably worse then NP-complete.
Pat
>
> --- Jan
>
>
> On 11/21/2012 08:05 PM, Tim Berners-Lee wrote:
>>
>> Literals in the *subject* position, on the other hand -- are very sensible.
>> I have listed reason for these before, and the discussion must be very
>> old so I'm
>> not inclined to go into them in great depth.
>>
>> "Fr." :isShortFor "France".
>>
>> 3 expressedAsAString "3".
>>
>> 12 :mutuallyPrime 35.
>>
>> "chat" :occursIn :English, :French.
>> Also we have inverses, which make any asymmetry
>> in what can be put in S and O positions lead to strange things,
>>
>> :foo :seconds 73.
>> :second owl:inverse :hertz.
>>
>> for example can be said but leads to an inference which
>> cannot be expressed if you can't put a number as a subject.
>>
>> Tim
>>
>> On 2012-11 -19, at 13:20, Jan Wielemaker wrote:
>>
>>> On 11/19/2012 07:13 PM, Pat Hayes wrote:
>>>> How about literals in subject position in a triple?
>>>
>>> I think it is the same story. Invites for
>>>
>>> "Paris" something:catipalOf "France"
>>>
>>> While we all know there are other ways to interpret
>>> "Paris".
>>
>> Yes, but I think your example makes clear:
>> What on earth makes you suppose form this example that
>> there is any difference between the needs for subject and the needs for
>> objects?
>>
>> Clearly, by this thinking, literals should due dial allowed in the
>> object position too!
>>
>>
>>
>>
>>
>>> I think we are doing right to allow for
>>> literals only in the object position.
>>>
>>> Cheers --- Jan
>>>
>>
>
>
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